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Edendale
14-05-2021, 11:44 AM
I have a denford microrouter that just been converted to Mach3, everthing seemed to work ok but 5 minutes into the first job it suddenly stopped and the y axis sounded like a machine gun, I tried to move the y axis with the keyboard it won’t move & just keeps making rattling sound, I reset the controller and it started to move ok until it stopped again and made the same rattling sound, could it be the stepper motor at fault or the ball nut, how would I find out which one is is causing the problem, also where could I find replacement parts, Thankyou. Mike2994629947

andy_con
14-05-2021, 12:35 PM
I have a denford microrouter that just been converted to Mach3, everthing seemed to work ok but 5 minutes into the first job it suddenly stopped and the y axis sounded like a machine gun, I tried to move the y axis with the keyboard it won’t move & just keeps making rattling sound, I reset the controller and it started to move ok until it stopped again and made the same rattling sound, could it be the stepper motor at fault or the ball nut, how would I find out which one is is causing the problem, also where could I find replacement parts, Thankyou. Mike2994629947

Have you oiled the ball screws and rails?

When was the last time it was oiled?

Edendale
14-05-2021, 01:48 PM
Yes oiled well and slides freely, I disconnected the stepper motor and ran a program and it still does it so looks like the motor or wiring may be the problem, do denford still carry spares for old machines ! Regards Mike

Clive S
14-05-2021, 02:24 PM
Yes oiled well and slides freely, I disconnected the stepper motor and ran a program and it still does it so looks like the motor or wiring may be the problem, do denford still carry spares for old machines ! Regards Mike


It could be the drive or cabling First is to check with a meter both phases of the stepper post a picture of the drive and connections to the stepper there will be 4 wires to the stepper ie 1 pair for each coil.

It is unusually for a stepper to fail.

Don't unplug the stepper with the drive powered

Edendale
14-05-2021, 02:39 PM
Thanks Clive, it would appear that it is the cable going into the motor, as it moves there must be a break in the wire, it looks like the wiring is connected directly to the windings so not sure if it’s the cable or the thin copper wire on the winding that’s the problem, I’ll have a look tomorrow, ��

andy_con
14-05-2021, 04:52 PM
Thanks Clive, it would appear that it is the cable going into the motor, as it moves there must be a break in the wire, it looks like the wiring is connected directly to the windings so not sure if it’s the cable or the thin copper wire on the winding that’s the problem, I’ll have a look tomorrow, ��

I had a cable break on my Denford triac, so it does happen.

It was the cable going into the stepper, not the stepper wiring

Clive S
14-05-2021, 05:22 PM
Thanks Clive, it would appear that it is the cable going into the motor, as it moves there must be a break in the wire, it looks like the wiring is connected directly to the windings so not sure if it’s the cable or the thin copper wire on the winding that’s the problem, I’ll have a look tomorrow, ��

Don't open the motor up. Did you check the ohms between each phase they should be around 1-2 ohms across each coil.

You are not giving any info back so it is hard to guess.

Edendale
15-05-2021, 10:30 AM
Hi Clive, your advice to not open the stepper motor came to late I’m afraid, but I have checked all wires, and I think the break is in the chain, looks like I’m going to have to replace all the wiring,

JAZZCNC
15-05-2021, 12:04 PM
Hi Clive, your advice to not open the stepper motor came to late I’m afraid, but I have checked all wires, and I think the break is in the chain, looks like I’m going to have to replace all the wiring,

Well, don't be surprised if it doesn't work properly when you do find the cause because they rarely work the same after being taken apart.

Edendale
15-05-2021, 03:09 PM
O dear, any idea where I buy a replacement from

cropwell
15-05-2021, 03:32 PM
Are there any markings on the failed motor?

Doddy
15-05-2021, 05:17 PM
I may have a Denford stepper - NEMA23 with circular body.... though to be honest you can replace with a fairly generic part.

EDIT: Ignore that - I don't *think* that stepper in the first picture is an OEM part (unless Denford had very different designs - may be the case over the years). That looks like a fairly generic stepper tbh.

andy_con
15-05-2021, 05:59 PM
Give us the number and there are many replacements out there

Edendale
15-05-2021, 06:05 PM
Thanks Doddy, is the stepper I have a NEMA 23, this one has 8 wires but 2 pairs are joined to each other so a standard 4 wire stepper will be ok I assume, I have just been diagnosed early onset of Alzheimer’s & vascular dementia so I have a tendency to do things without thinking properly, appreciate everyone’s help, regards Mike 29954

Edendale
15-05-2021, 06:12 PM
2995529955

ZASto
16-05-2021, 08:24 AM
You can buy chinese motors from fleebay/amazon/ali, rg. 57HS76 - bipolar, 4 wires - which has holding torque of 1.1Nm (MAE has 0.98Nm)

Edendale
16-05-2021, 11:15 AM
Thankyou for that information, I replaced the a broken wire that was causing the initial fault but in doing so I caused a problem with the stepper, I should have realised as the last router I tried to fix coast me £700 and it was a broken wire

Edendale
16-05-2021, 11:57 AM
Found this one on Amazon,29963 would this one be ok please

ZASto
16-05-2021, 08:03 PM
That is the one :)

Edendale
16-05-2021, 08:34 PM
Thanks ��